Fermentative capacity of Saccharomyces and non-Saccharomyces in agave juice and semi-synthetic medium

ABSTRACTSaccharomyces cerevisiaesake yeast strain Kyokai no. 7 has one of the highest fermentation rates among brewery yeasts used worldwide; therefore, it is assumed that it is not possible to enhance its fermentation rate. However, in this study, we found that fermentation by sake yeast can be enhanced by inhibiting mitophagy. We observed mitophagy in wild-type sake yeast during the brewing of Ginjo sake, but not when the mitophagy gene (ATG32) was disrupted. During sake brewing, the maximum rate of CO2production and final ethanol concentration generated by theatg32Δ laboratory yeast mutant were 7.50% and 2.12% higher than those of the parent strain, respectively. This mutant exhibited an improved fermentation profile when cultured under limiting nutrient concentrations such as those used during Ginjo sake brewing as well as in minimal synthetic medium. The mutant produced ethanol at a concentration that was 2.76% higher than the parent strain, which has significant implications for industrial bioethanol production. The ethanol yield of theatg32Δ mutant was increased, and its biomass yield was decreased relative to the parent sake yeast strain, indicating that theatg32Δ mutant has acquired a high fermentation capability at the cost of decreasing biomass. Because natural biomass resources often lack sufficient nutrient levels for optimal fermentation, mitophagy may serve as an important target for improving the fermentative capacity of brewery yeasts.

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Heterogeneity of Size and Distribution of Intramembrane Particles in the Plasma Membrane of Yeast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080407 ◽

1977 ◽

Vol 35 ◽

pp. 596-597

Author(s):

E. Keyhani

Keyword(s):

Plasma Membrane ◽

Candida Utilis ◽

Synthetic Medium ◽

Freeze Fracture ◽

Translational Diffusion ◽

Yeast Cells ◽

Distilled Water ◽

Intramembrane Particles ◽

The Matrix ◽

Water Cell

The matrix of biological membranes consists of a lipid bilayer into which proteins or protein aggregates are intercalated. Freeze-fracture techni- ques permit these proteins, perhaps in association with lipids, to be visualized in the hydrophobic regions of the membrane. Thus, numerous intramembrane particles (IMP) have been found on the fracture faces of membranes from a wide variety of cells (1-3). A recognized property of IMP is their tendency to form aggregates in response to changes in experi- mental conditions (4,5), perhaps as a result of translational diffusion through the viscous plane of the membrane. The purpose of this communica- tion is to describe the distribution and size of IMP in the plasma membrane of yeast (Candida utilis).Yeast cells (ATCC 8205) were grown in synthetic medium (6), and then harvested after 16 hours of culture, and washed twice in distilled water. Cell pellets were suspended in growth medium supplemented with 30% glycerol and incubated for 30 minutes at 0°C, centrifuged, and prepared for freeze-fracture, as described earlier (2,3).

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Fermentative capacity of residual wine yeast

Acta Alimentaria ◽

10.1556/aalim.34.2005.2.12 ◽

2005 ◽

Vol 34 (2) ◽

pp. 187-191 ◽

Cited By ~ 1

Author(s):

L. Oprean ◽

N. Darie ◽

E. Gaspar

Keyword(s):

Wine Yeast ◽

Fermentative Capacity

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Performance of Different Solid and Liquid Culture Media for the Improvement of Tuberculin Production

International Journal of Veterinary Science ◽

10.37422/ijvs/20.013 ◽

2020 ◽

Keyword(s):

Culture Media ◽

Synthetic Medium ◽

Chemical Properties ◽

Economic Loss ◽

Delayed Type Hypersensitivity ◽

Basic Medium ◽

Primary Methods ◽

Lowenstein Jensen ◽

Time Required ◽

Modified Media

Tuberculosis (TB) is one of the most important zoonotic bacterial diseases. A huge economic loss which could be direct or indirect are associated with the disease. Currently, the primary methods used for detection of TB in humans and cattle include the measurement of a delayed type hypersensitivity to purified protein derivative (PPD). So, the need for preparation of purified PPD with adequate properties and increasing the final PPD yield with decreasing the time of tuberculin production has stimulated the interest in the development of its preparation. Our study was performed to compare between the standard and modified media for improving tuberculin production. Middle brook 7H10 agar medium was used as a modified basic medium for mycobacterial growth, followed by cultivation of mycobacteria on Middle brook 7H9 broth medium. For the production, strains were inoculated onto the culture medium (Dorest Henly synthetic medium). Other steps for tuberculin production was done according to standard Weighbridge protocol. The results demonstrated that the using of both Middle brook 7H10 agar and Middle brook 7H9 broth instead of Lowenstein-Jensen (LJ) and glycerin broth media which used in currently produced tuberculin, have better physical and chemical properties. In addition, reducing the time required for production by accelerating the time of microbial growth. Also, it was found that the tuberculin produced using modified media was slightly more potent or the same as currently tuberculin produced. So, both Middle brook 7H10 agar and Middle brook 7H9 broth media are recommended for production of tuberculin saving time and increasing potency of the product but more investigation was recommended for estimation types of protein present in both locally prepared and modified tuberculin.

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Activated carbon as a better habitat for water and wastewater treatment microorganisms

Water Science & Technology ◽

10.2166/wst.2000.0260 ◽

2000 ◽

Vol 42 (12) ◽

pp. 149-154 ◽

Cited By ~ 5

Author(s):

M. Okada ◽

H. Morinaga ◽

W. Nishijima

Keyword(s):

Batch Culture ◽

Bacterial Growth ◽

Membrane Filter ◽

Synthetic Medium ◽

Dialysis Tubing ◽

Water And Wastewater Treatment ◽

Batch Cultures ◽

K 12 ◽

Bacterial Yield ◽

Adsorption Desorption

Effects of PAC on bacterial activity were evaluated by sequencing batch cultures (20 hours each) of E.coli K-12 on synthetic medium containing glucose as a sole carbon source. Four suspended sequencing batch culture systems were operated; CP: cultures supplemented with PAC, CR: cultures with removal of metabolites by PAC at the end of each batch culture, CD: cultures supplemented with PAC in dialysis tubing to separate from E.coli, and CC: cultures without PAC (control). The supernatant of each batch culture was filtered through a membrane filter (0.2 μm) and was mixed with the same volume of fresh medium to be used as the medium for the next batch culture. The sequencing batch cultures were repeated three times for all the systems. The bacterial growth in CC was inhibited with the increase in the number of batch cultures. Although a significant amount of metabolites was accumulated in the 3rd batch culture of CC, little accumulation was noted in the 3rd batch culture of CP. No growth inhibition was noted in CP for all the batch cultures. The little differences in the bacterial yield and metabolite accumulation between CR and CD suggested that adsorption/desorption of metabolites with PAC did not play a major role in bacterial growth. PAC addition may partly stimulate the growth by the removal of growth inhibiting metabolites. However, the fact that CP showed higher yield than CR and CD indicated that the contact between bacteria and PAC plays a significant role in the growth of bacteria.

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Isolation of Rhodocyclus gelatinosus from poultry slaughterhouse wastewater

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132002000600007 ◽

2002 ◽

Vol 45 (4) ◽

pp. 445-449 ◽

Cited By ~ 11

Author(s):

Elisa Helena Giglio Ponsano ◽

Pedro Magalhães Lacava ◽

Marcos Franke Pinto

Keyword(s):

Carbon Source ◽

Photosynthetic Bacteria ◽

Synthetic Medium ◽

Poultry Feed ◽

Gram Negative ◽

Slaughterhouse Wastewater ◽

Rhodocyclus Gelatinosus

Four cultures of photosynthetic bacteria isolated from poultry slaughterhouse wastewater were identified as Rhodocyclus gelatinosus based on the following properties: reddish color of cultures in synthetic medium, presence of motility, slightly curved Gram-negative rods morphology, gelatin liquefying activity, utilization of citrate as carbon source and production of bacteriochlorophyl a and carotenoids of the spirilloxanthin alternative series. R. gelatinosus may represent a source of nutrients and pigments with application in poultry feed.

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Profile of Volatile Compounds of On-Farm Fermented and Dried Cocoa Beans Inoculated with Saccharomyces cerevisiae KY794742 and Pichia kudriavzevii KY794725

Molecules ◽

10.3390/molecules26020344 ◽

2021 ◽

Vol 26 (2) ◽

pp. 344

Author(s):

Gilson Celso Albuquerque Chagas Junior ◽

Nelson Rosa Ferreira ◽

Eloisa Helena de Aguiar Andrade ◽

Lidiane Diniz do Nascimento ◽

Francilia Campos de Siqueira ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Volatile Compounds ◽

Multivariate Analyses ◽

High Capacity ◽

Starter Cultures ◽

Cocoa Beans ◽

Pichia Kudriavzevii ◽

Fermentative Capacity ◽

Product Identity ◽

On Farm

This study aimed to identify the volatile compounds in the fermented and dried cocoa beans conducted with three distinct inoculants of yeast species due to their high fermentative capacity: Saccharomyces cerevisiae, Pichia kudriavzevii, the mixture in equal proportions 1:1 of both species, and a control fermentation (with no inoculum application). Three starter cultures of yeasts, previously isolated and identified in cocoa fermentation in the municipality of Tomé-Açu, Pará state, Brazil. The seeds with pulp were removed manually and placed in wooden boxes for the fermentation process that lasted from 6 to 7 days. On the last day of fermentation, the almonds were packaged properly and placed to dry (36 °C), followed by preparation for the analysis of volatile compounds by GC-MS technique. In addition to the control fermentation, a high capacity for the formation of desirable compounds in chocolate by the inoculants with P. kudriavzevii was observed, which was confirmed through multivariate analyses, classifying these almonds with the highest content of aldehydes, esters, ketones and alcohols and low concentration of off-flavours. We conclude that the addition of mixed culture starter can be an excellent alternative for cocoa producers, suggesting obtaining cocoa beans with desirable characteristics for chocolate production, as well as creating a product identity for the producing region.

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Microbiological Sulfide Removal—From Microorganism Isolation to Treatment of Industrial Effluent

Microorganisms ◽

10.3390/microorganisms9030611 ◽

2021 ◽

Vol 9 (3) ◽

pp. 611

Author(s):

Zhendong Yang ◽

Zhenghua Liu ◽

Aleksandra Sklodowska ◽

Marcin Musialowski ◽

Tomasz Bajda ◽

...

Keyword(s):

Elemental Sulfur ◽

Synthetic Medium ◽

Industrial Effluent ◽

Oxygen Demand ◽

Growth Yield ◽

Xrd Analysis ◽

Sulfide Concentration ◽

Leachate Treatment ◽

Metabolic System ◽

Sulfide Removal

Management of excessive aqueous sulfide is one of the most significant challenges of treating effluent after biological sulfate reduction for metal recovery from hydrometallurgical leachate. The main objective of this study was to characterize and verify the effectiveness of a sulfide-oxidizing bacterial (SOB) consortium isolated from post-mining wastes for sulfide removal from industrial leachate through elemental sulfur production. The isolated SOB has a complete sulfur-oxidizing metabolic system encoded by sox genes and is dominated by the Arcobacter genus. XRD analysis confirmed the presence of elemental sulfur in the collected sediment during cultivation of the SOB in synthetic medium under controlled physicochemical conditions. The growth yield after three days of cultivation reached ~2.34 gprotein/molsulfid, while approximately 84% of sulfide was transformed into elemental sulfur after 5 days of incubation. Verification of isolated SOB on the industrial effluent confirmed that it can be used for effective sulfide concentration reduction (~100% reduced from the initial 75.3 mg/L), but for complete leachate treatment (acceptable for discharged limits), bioaugmentation with other bacteria is required to ensure adequate reduction of chemical oxygen demand (COD).

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Metabolites of Aspergillus indicus: The structure and some aspects of the biosynthesis of dihydrocanadensolide

Australian Journal of Chemistry ◽

10.1071/ch9682775 ◽

1968 ◽

Vol 21 (11) ◽

pp. 2775 ◽

Cited By ~ 7

Author(s):

AJ Birch ◽

AA Qureshi ◽

RW Rickards

Keyword(s):

Succinic Acid ◽

Fumaric Acid ◽

Pyruvic Acid ◽

Kojic Acid ◽

Synthetic Medium ◽

Nitropropionic Acid

Aspergillus indicus grown on a semi-synthetic medium produces a number of metabolites including kojic acid, succinic acid, fumaric acid, β-nitropropionic acid, indazonic acids, fumaryl-~danine, and dihydrocanadensolide. The last compound is shown to have the formula (I) and is biosynthesized in part from "acetate" units; the rest of the molecule may come from pyruvic acid.

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